1. Field of the Invention
The present invention relates to detection devices such as sensors, and more specifically relates to techniques for arranging the main body of a sensor and a circuit component for detection.
2. Description of the Related Art
In accordance with the miniaturization and functional improvements of instruments, detection devices (sensors) installed in the instruments are required to have higher detection accuracy, be smaller and lighter, and operate at lower power consumption.
For example, video cameras or the like generally include angular velocity sensors for detecting angular variation due to shaking, and output signals from such sensors are used for compensating for the shaking. Since video cameras are becoming smaller every year and the detection accuracy of the sensors greatly affects the user-friendliness, the sensors are required to have high performance.
In addition, when the size of tilt sensors, rotational angle sensors, etc., is reduced and such sensors are installed in, for example, joysticks and gamepads for home-use game machines, virtual games or the like can be played without going to large amusement arcades.
Such requirements for miniaturization and functional improvements also apply to instruments other than mobile devices and game machines.
In such detection devices (sensors), the main body of the sensor and a circuit component which processes a sensor signal are generally formed separately, and a long electric line is necessary for connecting the main body of the sensor and the circuit component. Accordingly, the electrical signal detected by a detector unit is affected by external noise when it passes through the electric line. In addition, there is a possibility that the detection accuracy will be degraded due to the parasitic capacitance of the electric line.
On the other hand, capacitive sensors which use capacitance changes have been developed to satisfy the above-described requirements for high sensitivity, low power consumption, etc. However, small capacitive sensors have small capacitances, such as less than 1 pF and capacitance changes therein are extremely small, such as about 0.02 pF to 0.03 pF. Accordingly, there is a problem in that external noise as described above greatly affects the detection accuracy.